Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already disclose that this is a non-read-only, non-destructive, non-idempotent mutation. The description adds useful context about how global values are consumed, including a date-wait example. It does not disclose collision behavior when the key already exists, permission requirements, or whether creation fails on duplicate keys, which matters for a non-idempotent create.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two tight sentences that front-load the core purpose and then add the most relevant usage context. Every sentence contributes something an agent would not get from the tool name alone.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a five-parameter mutation tool with no output schema and only 40% schema description coverage, the description leaves several gaps. It communicates purpose and downstream usage well, but an agent still lacks guidance on duplicate keys, failure modes, and how type and value interact.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is low at 40%, so the description should compensate more. It adds operational meaning for the key reference syntax and date-value behavior, but does not explain the name, description, or how the value parameter must align with the selected type. The added semantics are useful but incomplete against the coverage gap.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific verb and resource: create a global value. It also explains how the created value is referenced as {{global.<key>}}, which helps an agent understand the tool's output context. It does not explicitly differentiate this from update-global-value or delete-global-value, but the create action is unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage by explaining that global values are referenced in templates and can be used in automation date waits. However, it does not state when to use this tool instead of update-global-value, or what to do if a value with the same key already exists. The guidance is contextual but not prescriptive.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.